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351.
西藏湿地的现状和保护 总被引:5,自引:0,他引:5
本研究对西藏全区湿地的概况、类型、现状、重要湿地和现有湿地保护区进行系统描述,提出了湿地保护方面存在的问题与对策;并对西藏湿地标准、功能、特点、类型等,进行了科学的论证。 相似文献
352.
地质勘探安全生产工作的思考与对策 总被引:4,自引:1,他引:3
通过对地质勘探行业安全生产工作现状和存在问题的分析和思考,从安全监管、制度建设、安全培训和事故处理等方面,提出了一些对策和建议,对改进地质勘探行业安全生产形势,提高勘查成果质量和地勘单位经济效益有着十分重要的意义. 相似文献
353.
张新海 《中国安全科学学报》2009,19(6)
针对传统交通事故动态分析法在交通肇事逃逸案件侦查中投入高、效率低、精度差的缺点,笔者在信息主导警务理念的指导下,综合运用逻辑学、系统科学、社会学、心理学、情报科学相关原理,动态分析交通事故现场的痕迹、车辆行驶轨迹、道路交通环境、警情综合信息、驾驶人行为与逃逸心理,以及受害者损伤特征,准确掌握车辆或驾驶人局部特征,从而为侦破交通肇事逃逸案件提供精确的查缉信息,使警务行动实现精确用警、快速反应和精确打击的目标。笔者给出了利用动态分析法侦破交通肇事逃逸案件的流程和步骤;指出提高办案水平,迫切需要加强警务信息和社会信息的有效融合,研发专门系统,强化信息研判。 相似文献
354.
湖北长江经济带的开放开发是在经济发展具有一定实力基础上的再开放再开发,只有以科技为主导,才能使其立足高起点,体现高水平,实现新突破,要始终把握“围绕一条主线,把握两个坚持,努力实现四化”的指导思想,着力建设湖北沿江高新产业带,星火技术密集带,信息公路网络带(一江三带),使湖北长江经济带成为我国中部的科技走廓,为此,要优化科技资源配置,提高研究开发投资水平,建设“八个中心”健全科技服务体系,完善宏观 相似文献
355.
Chao‐Hsien Liaw Yao‐Lung Tsai 《Journal of the American Water Resources Association》2004,40(4):901-912
ABSTRACT: Major parameters and optimum storage volumes of rooftop rain water harvesting systems (RRWHSs) have not been investigated in detail in Taiwan. Accordingly, the four major parameters of RRWHSs were herein identified and elucidated using a simulation method. Because the performance of the RRWHSs is sensitive to the runoff coefficient, a field experiment was conducted to determine the runoff coefficient more precisely for various types of roofs. A simulation model including production theory was developed and employed to estimate the most cost effective combination of the roof area and the storage capacity that best supplies a specific volume of water. Consequently, the expansion path of optimum solutions for different volumetric reliability of water supply can be determined. Additionally, the method based on the marginal rate of substitution can be used for determining the rational volumetric reliability. The procedures developed herein constitute an effective tool for preliminarily estimating the most satisfactory storage capacity of any specific roof area and for determining the rational reliability of a corresponding water supply. 相似文献
356.
Leon Liegel David Cassell Donald Stevens Paul Shaffer Robbins Church 《Environmental management》1991,15(2):269-279
The Direct/Delayed Response Project (DDRP) is one of several studies being conducted by the United States Environmental Protection
Agency to assess risk to surface waters from acidic deposition in the eastern United States. In one phase of DDRP, land use,
wetland, and forest cover data were collected for statistical samples of 145 Northeast lake and 35 Southern Blue Ridge Province
stream watersheds in the United States. Land-use and other data then were extrapolated from individual to target watershed
populations. Project statistical design allows summarization of results for various subsets of the target population. This
article discusses results and implications of the land-use and land-cover characterization for both regions.
Forest cover was the primary land use in both regions. In the Northeast, developed (agriculture and urban) land was positively
associated with surface-water chemistry values for acid neutralizing capacity, Ca plus Mg, pH, and sulfate in the Pocono/Catskill
subregion. Extensive wetlands and beaver activity occur in parts of the Northeast region, whereas topography limits wetland
and riparian development in the Southern Blue Ridge Province. Northeast soils have low sulfate adsorption capacity, most watersheds
are near sulfur steady state, and lake sulfate concentrations are controlled principally by levels of sulfur deposition. Net
annual sulfur retention in Northeast watersheds is positively correlated with occurrence of wetlands and beaver impoundments.
In contrast, most Southern Blue Ridge Province soils have high sulfate adsorption capacities, resulting in high net watershed
sulfur retention. At the present time, stream sulfate concentrations and percent sulfur retention are controlled principally
by soil chemical properties related to adsorption rather than atmospheric deposition and land use.
The information in this document has been funded wholly by the United States Environmental Protection Agency. It has been
subjected to the agency's peer and administrative review, and it has been approved for publication as an EPA document. Mention
of trade names or commercial products does not constitute endorsement or recommendation for use. 相似文献
357.
Saiful Arif Abdullah 《环境科学学报(英文版)》2003,15(2):267-270
This paper presents the pattern and changes of fragmented forest in relation with changes of total forest cover in the state of Selangor in three decades.In this study,inventoried forest cover maps of Selangor in 1971/1972,1981/1982 and 1991/1992 produced by the Forestry Department of Peninsular Malaysia were digitized to examine the changes in area and number of fragmented forest.Results showed that in 1971/1972,16 fragmented forests were identified in Selangor.All fragmented forests were identified as diptercoarp forest.A decade later the number of fragmented forests increased by approximately 44%(23).Of the 23 fragmented forests,two were peat swamp forests whereas the remaining were dipterocarp forests.In 1991/1992 the number of fragmented forests(12)was reduced by 47.8%.Two of the fragmented forests were Fragmentation of both dipterocrp and peat swamp forests occurred profoundly during the period between 1971/1972and 1981/1982,which consequently increased the number of fragmented forests compared with before the period of 1971/1972 where fragmentation happened only at dipterocarp forests.However,many fragmented forests vanished between the 1981/1982 and 1991/1992 periods. 相似文献
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